Tuning without lamda!

Understanding AFR

Most of OFF ROAD car without o2 sensor , how can read lamda ? You said by arf but the petrol pump have 91 95 96 octan , so, maybe it's not 14.7AFR, or maybe one persone come with Q16 how can be controller this (can explan) ? I buy afr gauge but i think not important should be buy lamda gauge if available!

In order to tune the engine you will need to fit a wideband AFR meter. You can fit this temporarily just for tuning and then remove it, or you can leave it permanently fitted. Pump fuel regardless of octane rating is considered to have a stochiometric AFR of 14.7:1. If you use lambda instead of AFR units as recommended in this course, then the actual stoichiometric AFR of the fuel won't matter - Lambda 1.00 is always stoichiometric.